This paper describes how a microphone plugged in to a normal computer can be used to record the impacts of a ball bouncing on a table. The intervals between these impacts represent the "time of flight" of the ball. Since some energy is lost in each rebound, the time intervals get progressively smaller. Through calculation it is possible to calculate the percentage energy lost after each bounce, and by extrapolating backwards it is possible to estimate the height from which the ball was dropped. This "experiment" demonstrates how the equations of motion and the concept of inelastic collisions can be used together to describe the motion of a bouncing ball. Pupils can study energy losses and the behaviour of different types of ball and find out which type gives the closest agreement between the height calculated by the theory and that measured prior to dropping the ball.